Positive displacement pump of the constant delivery type



Nov. 26, 1935.

H. J. KRATZER POSITIVE DISPLACEMENT PUMP OF THE CONSTANT DELIVERY TYPE Filed Sept. 15, 1953 W mu Patented Nov. 26, 1935 POSITIVE DISPLACEMENT PUMP OF THE CONSTANT DELIVERY TYPE Herbert J. Kratzer, St. Louis, Mo.

Application September 15, 1933, Serial No. 689,595

3 Claims.

This invention relates to certain improvements in positive displacement pumps and has for one of its objects to provide a reliable and a noiseless pump of simple manufacture, having a large capacity-to size ratio.

Another object of the invention is to provide a positive displacement pump wherein a minimum of surfaces friction.

A further object of the invention is in providing a pump of the constant delivery type with improved means in its construction whereby the operative parts compensate for natural wear, thus providing for efficient operation over a long service life.

A still further object of the invention, is in providing a positive displacement pump with improved means for compressing the charge prior to the displacement thereof.

Other and further objects will appear in the specification and be specifically pointed out in the appended claims, reference being had to the accompanying drawing, exemplifying the invention, and in which:-- I

Figure 1 is a longitudinal vertical section taken through this improved positive displacement pump on the line II of Fig. 2.

Figure 2 is a transverse vertical section taken approximately on the line II-II of Fig. 1.

Figure 3 is an enlarged fragmentary transverse section taken through a portion of the rotor and one of the vanes thereof.

Figure 4 is a schematic view of the vane as-' sembly and the hinges thereof to the supporting axis.

Referring by numerals to the accompanying drawing, I designates a housing which comprises a cylindrical body 2 having end members 3 and 4, said body and end members being secured together by the tie bolts 5. The body 2 is provided on opposing sides with an intake connection and a discharge connection I.

Longitudinally disposed for operation within the housing I is a vane operating rotor 8 having end members 9 and I0, each being supported on a respective anti-friction bearing II. The end member 9 of the rotor 8 is provided with a tubular extension I2 which extends through the end member 3 of the housing I, and fixed on said tubular extension beyond the end member 3 is a driven pulley I3. 1

The end member 9 of the rotor 8 and the end member 3 of the housing I, are designed so that an end thrust bearing I4 is cooperably disposed therebetween.

The rotor 8 is built from a plurality of longitudinal circumferential sections I5 which are circumferentially separated from each other for providing longitudinal gaps I6, each section I5 having end flanges I? through which rivets I8 are I passed for securing the sections to respective end 5 members 9 and I9.

Each section I5 on respective longitudinal edges, is provided with a longitudinally extending groove I9, and mounted in each groove is a strip of non-growing packing 26, each packing 10 V strip 29 extending into a gap I6.

Longitudinally disposed in the rotor 8 and disposed eccentric thereto, is a shaft or member 2|, said shaft being disposed concentrically in the housing I and is formed integral at one end with an arm 22 of a horizontal supporting portion 23. The opposite end of the shaft 2| is secured to an arm 24 by a pin 25, said arm 24 being integral with a horizontal supporting portion 26. The supporting portions 23 and .29 of the shaft 2| are disposed in horizontal alinement and are mounted through respective bearings I I and end members 9 and It of the rotor 8, the supporting portion 26 of the shaft 2| extending through the tubular extension I2 of the end member 3 of the 25 housing I, and having an end support 21 to which the supporting portion 26 is fixedly secured by the key 28. The supporting portion 23 of the shaft 2! is fixed to a bushing 29 by a key 30 and the bushing 29 being fixed to the end member 30 4 of the housing I by the cap screws 3|.

Mounted on the shaft 2i between the arms 22 and 24 thereof, is a bearing sleeve 32, and mounted on said sleeve area plurality of hinges 33 which are disposed in sets for the support of a plurality 35 of vanes or buckets 34, each vane extending through respective gaps I6 of the rotor 8 and between opposing pairs of packing strips 20.

One of the packing strips of each opposing pair of packing strips 29 is provided with a cooperating kinked leaf spring 35 for causing each spring related packing strip to follow up and continually engage respective vanes 34 against a respective opposed packing strip as the vanes are caused to slide between related pairs of packing strips during rotation of the rotor.

In the operation of the device, the pulley I3 upon being driven, will operate the rotor B in the direction of the arrow 36 shown in Fig. 2, and by reason of the shaft 2I supporting the hinges 33 to which the vanes 34 are secured, the vanes 34 of which there are four, will be traveled with the rotor in wearing contact at their outer ends with the inner periphery 31 of the housing I. During travel of the vanes with the rotor, the fixed eccentric relation of the shaft 2| with the rotor will cause the vanes to spread a greater distance apart between cooperating pairs on the intake or suction side of the device and will further cause the cooperating pairs of vanes to be moved towards each other on the discharge side of the device. This action is brought about by reason of the fixed shaft 26 being disposed concentric to the housing and in alineinent with the intake and discharge connections 3 and i, and the rotor being eccentrically disposed in the housing on an axis at a right angle to the intake and discharge con- I nections, and the periphery of the rotor having a minimum clearance with the inner periphery of the housing.

With the above arrangement and disposition of parts, it will be seen from an inspection of Fig. 2 that the vane further designated as 34a has just cleared the opening of the intake connection 6, therefore an intake pocket A is determined between the vane 33a and the vane 34b into which fluid will be entrained from the intake opening as the vane 34a is caused to spread or move from the vane 3 and the spread of the vane 34a will continue until it reaches the approximate position shown at and during which time the vane 3 th reached the former position of vane 34a and in which position the vane 34?) will have cut off further suction or intake charging. The spreading and faster swinging during travel of the vanes from the positions 340. to 340 is caused by the peripheral travel of the rotor being in closer proximity to the shaft or hinge support 2 When a vane reaches the approximate position 7 shown at the, it will begin to move more slowly bv reason of the fulcrum point of contact of the rotor with the vane 34c shifting outwardly on the vane, and whereas the vane 34a will be moving faster towards vane 340 on account of the fulcrum point of contact of the rotor therewith being inward, the retarding action of vane 34c and the quicker moving forward action of 34a, compressing the fluid between the vanes 34a and 34-0, and the compressing action on the fluid will continue until the vanes 34: and 340 simultaneously reach the approximate positions shown in dotted lines and designated as 3401 and 346, re-

spectively.

Continued travel of the vanes now designated as 341d and 34e will communicate the compressed fluid charge between said vanes with the discharge opening of the discharge connection 1 into which the compressed fiuid will be discharged.

Adjacent the intake side of the housing, a pocket 38 is formed for providing early loading of the fluid from the intake connection 6 behind each vane 34 as each vane travels into communication with the pocket. The opposite side of the housing i is provided with a pocket 4|ladjacent the opening of the discharge connection 1, this pocket providing for complete discharge of the compressed fluid between pairs of operating vanes.

With further regard to the pockets 38 and 4B,

' as shown in Fig. 2, attention is directed to the fact that a minimum of compressed fluid will be transferred from the pressure side of the housing to the suction side during the interval that the vanes are passing the dead sector of the housing.

During assembly of the device, the fixed shaft 2| on which the hinges 33 of the vanes 34 are supported, is mounted within the rotor 8 with the vanes there attached before the rotor is mounted in the housing In this connection, the sections I5 of the rotor are first secured to the end member 9 by the rivets I8, and the sleeve 32 is next mounted on the shaft 2| before the shaft is pinned to the arm 24 ready for the reception of the hinges 33 of the vanes 34.

Each vane 34 is provided with three hinges 33, 5 the hinges being arranged on each vane in a relation wherein they will stagger the hinges of other vanes when the hinges are mounted on the shaft 2|. After the vanes through their hinges have been mounted on the shaft 2|, the extend- 10 ing end of the shaft is then mounted in the arm 24 and secured thereto by pin 25, and the supporting portion 26 of the arm 24 is mounted in the tubular extension I2 of the end member 9 of the rotor it. During the mounting of the shaft in the rotor, care is taken to dispose each vane 34 in a respective gap IS. The end member I0 is then mounted over the supporting portion 23 of the shaft 2| and secured to the rotor sections l5 by the rivets I8, after which the packing strips 26 are mounted in respective grooves H] of the sections Hi. This completes the assembly of the rotor and the vanes 34 thereof ready for mounting it in the housing and for securing the driving pulley i3 to the tubular extension l2 of the rotor end member 9.

After the rotor 8 with the assembled vanes 34 has been mounted in the housing, the bushing 29 is then inserted in the end member 4 of the housing and secured thereto by the cap screws 3|. 30 The keys 28 and are then fastened in the keyways of respective supporting portions 23 and of the shaft 2| for fixedly securing said shaft against being turned in the bushing 29 and the end support 21.

The packing strips 20 are of the approximate length of the sections l5 of the rotor 8 and are adapted to engage respective inner surfaces of the end members 3 and 4 of the housing I.

The packing strips 20 will provide efficient packing of respective cooperating vanes 34, particularly in view of the fact that one of the packing strips 20 of opposing pairs of packing strips is resiliently and yieldingly held against a respective vane by a cooperating kinked leaf spring 35.

The vanes 34 are of a length so as to be in approximate wearing contact with inner faces of respective end members 3 and 4 of the housing and the extending end of each vane 34 is also adapted to be in approximate wearing contact with the inner periphery 31 of the cylindrical body 2 of the housing I so that cooperating pairs of vanes 34 will be efficient in compressing fluid charges therebetween as the fluid charges are conveyed from the intake side to the discharge side of the housing.

In the event of bearing wear on the hinges 33 of the vanes 34 and/or the sleeve 32 and the shaft 2|, centrifugal force will carry and hold the vanes outwardly, thus the wear Will be compensated for by reason of the outer edge of each vane contacting with the inner periphery 31 of the housing whereby the contacting edge of each vane will automatically wear to size.

Each of the end members 9 and In on their inner sides is counter-bored to provide an annular shoulder 4|, and in engagement with the shoulder of each end member, is an extending lip 42 formed on each end of each section l5 of the rotor, the under-engaging of the lips 42 of the sections l5 of the rotor, providing reliablemeans for carrying the centrifugal stress of the sections into the end members extraneous of the rivets l8.

A displacement pump of this improved character it is clear, can be ideally used for charging the cylinders of two-cycle motors as well as being useful for serving as a super-charger to a four-cycle motor, and in addition, the device can be used in operation as an independent unit for providing an air pressure for sand blasting and the like, or for any other purpose where a required pressure or partial vacuum is desired.

Having thus described my invention so that those skilled in the art will be able to practice the same, what I desire to secure by Letters Patent is defined in What is claimed, it being understood that various changes in the displacement pump shown and described above in detail and not amounting to invention may be made without departing from the spirit and scope of my invention.

What I claim is:

l. A rotor for a displacement pump comprising end members each having a laterally projecting internal annular shoulder, circumferentially spaced longitudinal sections having end projecting lips, said sections being secured to said end members with their projecting lips under-engaging respective annular shoulders of the end members, said end members being of less diameter than the circumferentially spaced sections at vane extending through the space between pairs of sections, and a longitudinally disposed shaft within the rotor to which the inner ends of the vanes are turnably secured.

2. A pump comprising a housing having recessed ends, a rotor in said housing comprising circumferentially disposed spaced sections having end projecting lips and end members of less diameter than said circumferential sections, each end member having an internal shoulder under which the projecting lips of said circumferential 5 sections are engaged and secured, a vane extending through the space provide-d between pairs of circumferential sections, means within the rotor for supporting the inner ends of said vanes, each end member of the rotor being disposed in a recess of the respective housing ends, and a packing strip engaging each side of each vane and having end abutment with the inner surface of respective housing ends outwardly of respective recesses thereof.

3. A displacement pump comprising a housing having eccentrically recessed end members, a rotor in'the housing having end members disposed in the respective recesses of the housing and members, spaced gaps formed in the periphery of the rotor, a vane of the approximate length of the housing extending through respective gaps of the rotor, the periphery of the rotor through which the vanes extend being of larger diameter than the end members thereof, a packing strip in each gap on each side of a respective vane, said packing strips having end abutment with the inner surface of respective housing end members outwardly of the end members of the rotor, and a support for the vanes disposed longitudinally in the rotor and held in eccentric position thereto.

HERBERT J. KRA'I'ZER. 

